import java.util.Scanner;

public class ComputeArea
{
	public static void main(String[] args)
	{
		Scanner input = new Scanner(System.in);

		System.out.print("Enter a number for radius: ");

		double radius = input.nextDouble();

		double area = radius*radius*3.14159;

		System.out.println("The area for the circle of radius " + radius + " is " + area + ".");
	}
}